Open Calculators
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Client-Side Computing & Zero Data Retention

Privacy Policy

Last Updated: September 17, 2026 • Effective Immediately

Educational, Illustrative & Informational Service Scope

Open Calculators is an educational calculation utility platform. We do not offer banking accounts, loan brokerage, credit checks, or financial advisory agreements. Because our tools exist solely for educational, illustrative, and informational purposes, we have intentionally designed our software architecture so that you never need to share confidential personal financial records or personally identifiable information (PII) to use any calculator.

1. Client-Side Privacy: Your Numbers Stay on Your Device

When you enter numbers into our mortgage, compound interest, or car buy vs. lease calculators (such as home price, down payment, interest rate, annual salary, or vehicle cost), those calculations are executed entirely inside your web browser’s JavaScript engine.

What this means for your privacy:

  • No financial inputs are transmitted to our remote web servers.
  • No loan balances, credit estimates, or salary numbers are stored in our databases.
  • We never sell, rent, or monetize your calculation inputs to lenders, brokers, or marketing networks.

2. Information We Never Collect

To preserve user privacy and reduce digital exposure, Open Calculators does not require:

  • User accounts, usernames, or passwords.
  • Government identification, Social Security Numbers (SSN), or National Insurance Numbers.
  • Credit card numbers, bank account details, or payment credentials.
  • Credit reports, credit bureau scores, or formal loan applications.

3. Shareable URLs & Query Parameters

When you adjust inputs or click the Share Calculation button, the calculator updates the URL query string (e.g. ?price=48000&down=6000&rate=3.5) purely to allow you to bookmark, refresh, or send the calculation to a colleague or family member. These parameters are read on the client device and are not harvested or cataloged by our systems.

4. Local Storage, Cookies & Advertising Partners

Open Calculators uses minimal, non-intrusive client-side storage technologies to deliver core utility functionality and sustainably fund free access:

User Interface Preferences: We use your browser’s local storage to remember your theme preference (Dark Mode vs. Light Mode) and previously selected currency format.
Privacy-Focused Analytics: We may utilize lightweight, privacy-respecting analytics services (such as Cloudflare Web Analytics) that do not track users across websites, do not construct cross-device profiles, and anonymize IP addresses.
Third-Party Advertising & Google AdSense: Third-party vendors, including Google, use cookies and/or web beacons to serve advertisements based on a user’s prior visits to this website or other websites. Google’s use of advertising cookies enables it and its partners to serve ads to our users based on their visits to our site and/or other sites on the Internet.

Your Advertising Choices & Cookie Opt-Out:

Users may opt out of personalized advertising by visiting Google Ads Settings. Alternatively, you can opt out of third-party vendor cookies for personalized advertising by visiting www.aboutads.info or the European Interactive Digital Advertising Alliance (EDAA) at youronlinechoices.com.

5. Global Privacy Compliance (GDPR, Swiss FADP, CCPA/CPRA)

Because Open Calculators serves a global audience across Switzerland, the European Union, the United States, the United Kingdom, Canada, and Australia, we adhere to the world’s strictest data protection standards:

  • European Union (GDPR / ePrivacy): Processing is limited to legitimate technical delivery of requested calculator pages. No non-essential profiling cookies are set without consent.
  • Switzerland (Revised FADP / nDSG): Data processing transparency and Swiss personal privacy mandates are strictly observed.
  • California (CCPA / CPRA): We do not sell or share personal information for cross-context behavioral advertising.

Contact Our Privacy Officer

If you have questions regarding our client-side computing architecture or data protection practices, please contact our data governance team at:

contact@opencalculators.app